四川理工学院毕业设计
某中型货车悬架总成设计
学 生：吴承明 学 号：0801103A279
专 业：机械设计制造及其自动化 班 级：车辆2008.3 指导教师：郭翠霞
四川理工学院机械工程学院
二O一二年六月
摘要
悬架是保证车轮或车桥与汽车承载系统之间具有弹性联系并能传递载荷、缓和冲击、衰减振动以及调节汽车行驶中的车身位置等有关装置的总称。悬架最主要的功能是传递作用在车轮和车架之间的一切力和力矩，并缓和汽车行驶过不平路面时所产生的冲击，衰减由此引起的承载系统的振动，以保证汽车行驶的平顺性。
尽管一百多年以来汽车悬架从结构形式到作用原理一直在不断地演进，但从结构功能而言它都是由弹性元件、减振装置和导向机构三部分组成。在有些情况下，某一零件部件兼起两种或三种作用，比如钢板弹簧兼起弹性元件及导向机构的作用。
本文讨论了汽车悬架的发展现状，对悬架的结构形式进行简单介绍，对影响悬架运动的各种因素进行分析，主要对中型货车板簧悬架的主要参数进行设计计算，包括中型货车前桥钢板弹簧、后桥复合式钢板弹簧、汽车减振器参数的选择计算和横向稳定杆的设计计算。为进一步设计板簧悬架提供了较有价值的资料。
关键词：悬架；钢板弹簧；减振器
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Abstract
Suspension involves some related components, which exist to guarantee elastic contact between wheels or axle and the carrying system. It also has a great contribution in transferring the load, cushioning the impact, attenuating vibration, and regulating the position of the body of the running car. Apart from the transformation of force and moment between wheels and frame, it help cushion the impact when uneven road surface is encountered, undermine the following vibration of carrying system, and as a result, provide a great possibility of smoothly running.
Despite one hundred year of constant evolution from structure to function, suspension is always made up by elastic component、vibration-absorbing appliance and guide mechanism. There will always be some occasion when one component plays two or more important roles at the same time. For example, plate spring can do some job which should be the duty of elastic component or guide mechanism.
This paper discusses the current development of vehicle suspension, gives a brief introduction of the structural form of suspension, analyze factors which have influence on suspension movement. The major part of this paper are calculation and design of leaf spring on front axle of medium truck、combined leaf spring on rear axle, stabilizer bar, as well as choosing the parameters of shock absorber. All of these are preconditions to further design of suspension with leaf spring.
Keywords: Suspension; leaf spring; shock absorber
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目 录
摘要................................................................................................................................. I Abstract ........................................................................................................................ II 第1章 绪论 ............................................................................................................... 1 第2章 总体设计 ....................................................................................................... 1
2.1 轴数、驱动形式、布置形式 .................................................................................................... 2 2.2 汽车主要参数设计 ................................................................................................................... 2
2.2.1主要尺寸 .......................................................................................................................... 2 2.2.2进行汽车轴荷分配 .......................................................................................................... 2
第3章 悬架系统的结构与分析 ............................................................................... 3
3.1 非独立悬架................................................................................................................................ 3
3.1.1非独立式悬架简介 .......................................................................................................... 3 3.1.2非独立式悬架特点 .......................................................................................................... 3 3.1.3 钢板弹簧式非独立悬架 ................................................................................................. 3 3.2 独立悬架.................................................................................................................................... 3 3.3 悬架主要参数的确定 ................................................................................................................ 4
3.3.1悬架的静挠度 .................................................................................................................. 4 3.3.2悬架的动挠度 .................................................................................................................. 5 3.3.3悬架主，副簧刚度的分配 .............................................................................................. 5
第4章 前悬架系统设计 ........................................................................................... 8
4.1钢板弹簧的设计计算 ................................................................................................................. 8
4.1.1 初选参数 ......................................................................................................................... 8 4.1.2钢板弹簧各片长度的确定 ............................................................................................ 10 4.1.3钢板弹簧总成在自由状态下的弧高及曲率半径计算 ................................................ 11 4.1.4钢板弹簧总成弧高的核算 ............................................................................................ 13 4.1.5钢板弹簧强度核算 ........................................................................................................ 14
4.2减震器的设计计算 ............................................................................................... 15
4.2.1减振器的选择与分类 .................................................................................................... 15 4.2.2减振器相对阻尼系数 .................................................................................................... 15 4.2.3减振器阻尼系数δ的确定 ............................................................................................ 16
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4.2.4最大卸荷力的确定 ........................................................................................................ 17 4.2.5筒式减振器工作缸直径D的确定 ............................................................................... 17 4.2.6查表确定减振器参数 .................................................................................................... 18
第5章 后悬架系统设计 ......................................................................................... 19
5.1 钢板弹簧的布置方案选择 ...................................................................................................... 19 5.2钢板弹簧主要参数的确定 ....................................................................................................... 19 5.2.1满载弧高 ........................................................................................................................ 19 5.2.2钢板弹簧长度L的确定 ............................................................................................... 19 5.2.3钢板弹簧断面尺寸的确定 ............................................................................................ 19 5.3 钢板弹簧各片长度的确定 ...................................................................................................... 22 5.4钢板弹簧刚度的验算 ............................................................................................................... 24 5.5钢板弹簧总成在自由状态下的弧高及曲率半径计算 ........................................................... 26 5.5.1钢板弹簧总成在自由状态下的弧高 ............................................................................ 26 5.5.2钢板弹簧总成在自由状态下的曲率半径的确定 ........................................................ 26 5.5.3钢板弹簧各片自由状态下曲率半径的确定 ................................................................ 27 5.5.4主簧总成和副簧总成各片在自由状态下弧高的计算 ................................................ 28 5.5.5钢板弹簧总成弧高的核算 ............................................................................................ 29 5.6钢板弹簧强度验算 ................................................................................................................... 30 5.7钢板弹簧主片的强度的核算 ................................................................................................... 31 5.8钢板弹簧弹簧销的强度的核算 ............................................................................................... 32
第6章 结论 ............................................................................................................. 33 参考文献 ..................................................................................................................... 34 致谢.............................................................................................................................. 35
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